Louis Antoine Marie Joseph Dollo was a Belgian palaeontologist, known for his work on dinosaurs. He also posited that evolution is not reversible, known as Dollo's law. Together with the Austrian Othenio Abel, Dollo established the principles of paleobiology.

Othenio Lothar Franz Anton Louis Abel was an Austrian paleontologist and evolutionary biologist. Together with Louis Dollo, he was the founder of "paleobiology" and studied the life and environment of fossilized organisms.